1. Field
The present disclosure relates generally to icing conditions and, in particular, to simulating icing conditions. Still more particularly, the present disclosure relates to a method and apparatus for simulating icing conditions in which supercooled large drops are present.
2. Background
In aviation, icing on an aircraft may occur when the atmospheric conditions lead to the formation of ice on the surfaces of the aircraft. Further, this ice also may occur within the engine. Ice formation on the surfaces of the aircraft, on inlets of an engine, and other locations is undesirable and potentially unsafe for operating the aircraft.
Icing conditions may occur when drops of supercooled liquid water are present. In these illustrative examples, water is considered to be supercooled when the water is cooled below the stated freezing point for water but the water is still in a liquid form. Icing conditions may be characterized by the size of the drops, the liquid water content, the air temperature, and/or other parameters. These parameters may affect the rate and extent at which ice forms on an aircraft.
Drops of water may be supercooled in various environments. For example, drops of water may be supercooled in stratiform clouds and in cumulous clouds.
When icing occurs, the aircraft may not operate as desired. For example, ice on the wing of an aircraft will cause the aircraft to stall at a lower angle of attack and have an increased drag.
Aircraft may have mechanisms to prevent icing, remove ice, or some combination thereof to handle these icing conditions. For example, aircraft may include icing detection, prevention, and removal systems. Ice may be removed using bleed air, infrared heating, and other suitable mechanisms.
Aircraft may have sensor systems designed to detect icing conditions. As new regulations are developed with respect to icing conditions that should be detected, manufacturers design and test sensor systems for detecting the icing conditions. For example, aircraft may be required to be certified to operate in normal icing conditions and in supercooled large drop icing conditions.
In designing and testing sensor systems, currently available test environments may not provide an ability to simulate supercooled large drop icing conditions in the manner desired to test new sensor systems. Therefore, it would be desirable to have a method and apparatus that takes into account at least some of the issues discussed above as well as possibly other issues.